Pin-tumbler lock



April 3o, 1940.

B. c. sMrr'H A PIN-TUMBLER LOCK Original Filed April 22, 1937 n//IHMK w My.A wf/aune www..

n l l l. 'IIIIIIIIIIIIMII gli 1I.

Patented Apr. 30, 194C UNITED STATES PIN-TUimLER LOCK- Bernard Smith, Brooklyn, N.Y.

Continuation of .application Serial No. 138,439,` April 22, 1937. This application March 14, 1939, Serial No. 261,809

6 `Claims.

Ihis invention relatesto improvements in locking mechanisms, and more particularly to pintumbler locking mechanisms. The present application is a continuation of my application for Heretofore, pin-tumbler locks have been regarded as being substantially invulnerable, but with the development of various unauthorized methods of opening locksby trickery, such as sense of touch, sense ci hearing, drop on shackle, tap system, spurious keys, picking, etc., all commonly known to experts and very easily applied, the conventional pin-tumbler locking principle can no longer be considered safe and secure. For example, in picking a lock of the pin-tumbler principle, the intruder will insert a tension tool into the keyway so as to exert a tension or leverage on theplug upon the 0 application of pressure with one; hand and permitting the other hand to apply a picking tool for aligning the pins so that the iirst hand with the tension tool may revolve the cylinder plug for opening the lock. 'I

The primary object of thepresent invention is to provide a pin-tumblerlocking mechanism so constructed that it cannot be operated b-y trickery, either by picking? or any other secret baffling system of unauthorized manipulation and which is therefore deiinitelyl pick-proof.

A further object is to provide an improved pintumbler locking mechanism havingr a sectional locking plug so constructed as to foil any attempt to apply tension or leverage to the plug by means of a tension tool. i

A still further object of the invention is the provision of baiiiing means for preventing joining of the sectional locking yplug by drilling,

Another object is to provide an improved pintumbler lock including a sectional locking plug having a normal locking position and an emergency locking position. v

Still another object is to provide an improved rotary locking plug construction for use'inconjunction with either a rim or a mortise lock.

Another object of the invention is to provide an improved sectional cylinder locking plug including a rear plug section having a keywayrchannel of abnormal width along its base and a baffling 0 wall or ward at the end of the keyway channel.

Another object of the invention is to provide a pin-tumbler lock mechanism including a sectional locking plug normally rotatable, by thev use of either-of two types of keys, one type of key patent, Serial Number 138,439, iiled April 22,.

being termed the guestf or maids key, and

(Cl. 'Y0-341) lthe other type of'key being termed the master or emergency lock-out` key.

Another object of the invention is to provide a pin-tumbler `lock mechanism including a sectional lockingplug including a front plug cylinder section independently rotatable toand :from a normal and an emergency lock-out position by means -i the aforesaid emergency lock-ou key and to the exclusion of the holder of the guest key at the will of the holder of the emergency lock-out key.

Other objects .and advantages of the invention will be apparent from the following detailed description, vtaken in connection with the accompanying drawing, forming a part of this specication and in whichdrawing':

Figure l is a View in iront elevation of the outer face of the improved lock and showing the rotary plugthereoi by means of full and dash lines in its normal andits emergency lock- K Fig. 3 is a top plan view of the improved lock. Fig. 4 is a vertical sectional View taken on the line 1 -lof Fig. 3.

Figs. 5 and 6 are views in side elevation of the guest and emergency lock-out types of keys respectively. l n

Fig. '7 is a longitudinal vertical sectional view taken on the line l-l of Fig. 3 and showing the relation of parts upon a full insertion of the emergency lock-ou key. i

Fig. 8 is a view similar to Fig. 7 but showing the relation of parts upon a partial insertion of the emergency lock-out key.

Fig. 9. is a view similar to Fig. 7 but showing the relation of` parts upon insertion of the guest key.

Fig. 10 is a bottom plan view of a sectional rotary plug forming apart of the present invention.

Fig. 11 is a vertical sectional view taken on the line I E-i l of Fig. l0 and showinga baffling washer vmounted in the plug. v

Fig. 12 is a View similar to Fig. `2'but showing a rim type of connecting element removably secured to the rotary plug. y

Fig. 13 is a View in side elevation of the rim type of connecting element.

Fig. lfl is a section on the line M-Il of Fig. 10.

In the drawing, which shows only a preferred form of pin-tumbler lock with its guest and emergency lock-ou keys, as well as preferred and modied forms of motion transmitting elements for detachable connection to the rotary plug, the letter A may generally designate the improved lock consisting of a frame, housing or casing B carrying a sectional rotary plug C, pintumbler locking means D for locking the rear section of the plug C, pin-tumbler locking means E for locking the front section of the plug C in a normal position, and pin tumbler locking means F for locking the front section of the plug C in an abnormal or emergency position. The guest key and the emergency lock-ou key may be designated G and H respectively while the mortise and rim types of motion transmitting elements for transmitting the rotary motion ofthe plug C may be designated J and K respectively.

The casing B may include a hollow cylinder l5 having the usual front or outer face I6 and provided with a radial rib l1 preferably extending vertically upwardly from the cylinder |5 and a second radial riby I8 preferably extending angularly upwardly from the cylinder.

In the cylinder i5 is the key receiving barrel or rotary plug C which includes a front section lil having a longitudinal slot or keyway 20 of conventional cross-sectional area, and provided with an intra-circumferential slot 2| having a substantially U-shaped base 22 in closely spaced adjacent relation to the keyway. The purpose of the slot 2| is to accommodate a disk-like balling washer 23 provided with a U-shaped notch 24 and so proportioned that the washer may be slid into the slot 2| about the keyway Z before the plug is mounted in the casing. Preferably, the washer is formed of steel or other suitable material sufficiently hardened-to successfully resist penetration by a drill or the like. At the inner end of the cylinder l5 is a rear plug section 25 in end to end axially aligning relation to the front section I9 and having a longitudinal slot or keyway 26 adapted to angularly align with the keyway 26 of the front section. However, the keyway 26 preferably differs from the conventional cross-sectional area of the keyway 20 in that the keyway 26 at its base portion 21 is abnormally wide as shown in Figures 10 and 14, and communicates with the upper portion 28 through the restricted slot 29. At the inner end of the rear plug section the upper portion 28 of the keyway terminates in a wall or Ward 3|] below which extends the widened base portion 2l of the keyway. The widened portion 2l extends throughout the length of the rear key receiving barrel or plug section 25 extending to the longitudinally extending shoulder |29.

Referring to the pin tumbler locking means D for locking the rear plug section, the same may include a row of drivers 3|, preferably three in number, mounted in openings of conventional cylindrical formation at the inner end of the radial rib and urged as by springs 32 into contact with the ends of a similar row of pins or pin-tumblers 33-33 mounted in radial openings in the rear plug section, upon proper angular alignment of the rear plug section in the casing. Preferably one of the pins 33 is composed of a master pin section 34 and a master disk section 34.

For locking the front plug section in a normal position, and in which position the keyway 26 is secured in alignment With the keyway 20 in its locked position, pin-tumbler locking means E is provided. The latter may include a row of drivers 35, preferably three in numb-er, mounted in openings of conventional cylindrical formation at the outer end of the radial rib H and urged as by springs 36 into contact with the ends of a similar row of pins 3l mounted in radial openings in the front plug section, upon proper fangular alignment of the front plug section within the casing.

The arrangement of the pin tumbler locking means D and E preferably is such that the rows of drivers 3| and 35 form a continuous line or series of drivers along the radial rib l'l while the rows of pins 33 and 31 form an interrupted line or series of pins along the rotary sectional plug C whereby a continuous keyway is formed which provides access to the locking means D and E when the front and rear plug sections are in their normal locked position.

Mounted in suitable cylindrical openings in the angularly disposed radial rib i8 and adapted to co-act with the pins 3l (which are common to each of the locking means E and F), upon predetermined angular rotation of the front plug section is a corresponding angularly disposed row of drivers 38 provided with suitable springs 39 and forming, in conjunction with the pins 3T, the pin tumbler locking means F for locking the front plug section in the emergency lock-out position, and in which position the keyway 2D is secured in angular disalignment with the locked position of the keyway 26 so that access to the pin-tumbler locking means D through the keyway 23 and intoI the keyway 26 is prevented.

The front and rear plug sections may each include a circumferential slot 40 accommodating the opposite ends 4| of a U-shaped retainer 42 swedged or pressed into the casing B so that the intermediate portion 43 see Fig. 8, will retain the springs 32 and 36 Within the rib 'I'he other rib I8 may be provided With a suitable slide 44 for retaining the springs 39.

As shown, in Figures 7 9, the length of each of the pins 33-33 of locking means D equals the length of its correspondingly positioned pin 3l common to each of the locking means E and F.

The guest key G is provided along its upper edge with a series of six pin-positioning notches, the rst three notches 45 inwardly of the free end of the keyblade being adapted to raise the two whole pins 33 and the master pin section 34 of the broken pin 33 so that their upper ends are brought into unlocking alignment along the cylindrical surface of the rear plug section. The other three notches 46 are adapted to raise the pins 3l so that their upper ends are brought into similar unlocking alignment along the cylindrical surface of the front plug section. While the pins 33-33 of the locking means D preferably correspond each to a similarly located pin 3'1 common to each of the locking means E and F, it willl be noted that in order to raise the master pin section 34 so that its upper end is flush with the surface of the plug, one notch of the series of notches 45 in the upper edge of the guest key will be positioned at a greater height than the similarly located notch of the series of notches 46, the difference in height being equal to the height or thickness of the master disk section 34' as shown in Fig. 9. This differentiation between the rst series of notches 45 and the second series of notches 46 of the guest key is sucient to prevent unlocking of the front plug section upon a partial insertion of the guest key in the keyway to a position in which the series of notches 45 at vthe free end of the key would co-act each 75 fic with one of the pins 31 common to each of the locking means E and F.

The emergency lock-out key H is provided valong its upper edge with a series of six pin-positioning notches, the first three notches 41 inwardly of the free end of the key-blade being adapted to raise the pins 33-33 so that their upper ends are brought into unlocking alignment along the cylindrical surface of the rear plug section, whilethe other three notches 48 serve to raise the pins 31 to an unlocked position. It will therefore be seen that, with the pins 33-33 of the locking means D each corresponding to a similarly located pin of the series of pins 31 of the locking means E, there need be no diierentiation between the series of notches Ai1 and the series of notches 43 of the emergency lock-out key. Thus, as shown in Figure "i, the emergency lock-out key H may be fully inserted in the keyv*ways 2t and 26 of both plug sections and will,

through the respective co-action of the notches l1 with the pins 33--33 and the notches 18 with the Apins 31, unlock both the locking means D and E and free the entireV plug for rotation by the key-blade. In addition, as shown in Fig. 8, the emergency lock-out keymay be partially inserted in the keyway so that, through the coaction of the notches 41' with the pins 31, the locking means E or the locking means F, depending on the angular position of the front plug section, will be released so that the front plug section may be turned by the keyblade independently of the rear plug section. In order to facilitate accurate cooperation of the notches 41 with the pins 31 when the emergency lock-out key I-I is utilized in its partially inserted position, a iiat strip 4S" provided at one end with a pivot 49 afxed to the handle end of the key, may be swung in a plane parallel to the keyblade so that its free end 5t is positioned along one side of the keyblade to form an abutment for limiting in- -sertion of the keyblade beyond a predetermined portion of the keyway. This abutment will contact the outer end or face of the cylinder plug.

In the back or lower edges 5l-52 oi the keys G and H respectively, there may be provided suitable niches 53-55 so that the retainer 42 will not obstruct the complete rotation of the plug.

At the rear end of the main body portion of the plug C, and preferably integral therewith is a rib-like connecting end portion 55 which may be provided'with a bifurcating slot 56 deiined by opposite side walls V51. each provided with a transverse notch 58 adapted to slidably receive a resilient loop-shaped retainer 59 at opposite sides 653 thereof. This retainer 59 may be employed for connecting to the plug either the mortise type yof motion transmitting element J or the rim type of motion transmitting element K. The element J may include a cam or roll-back portion 5i at one end and an attaching portion at the other end which may bel provided with a slot 66,

adapted to `accommodate the rib-like end portion 55 of the rear plug section. The attaching portion 62 may include a pair of side portions 64 at opposite sides of the slot vand which portions are adapted to abut the end of the main body portion of the yplug C upon` interlocking of the rib-like end portion 55 with the attaching portion E2 or" the element J at the slot 63. y y

The loop-shaped retainer 59 may then be slidably inserted in the transverse notches `58 so that the opposite ends 65 thereof will bear each upon one of the side portions 64 whereby to hold the element J'in its interlocking position.

As for the rim type of ymotion transmitting element K, it'may include an elongated spindle portion 66 having at one end 61 a pair of laterally ally of the 'bifurcating slot 56 so that upon align- .f

ment of the loop-shaped retainer encircling the spindle ywith the transverse notches 58, the end 61 may be slid into the bifurcating slot 56 and at the same time the retainer 59 will slide into the notches 58. Byr this procedure, the element K will be interlockingly secured to the plug C with its side portions 68 held in abutting relation to the end of the main body portion of the rear plug section by the opposite ends 65 of the retainer 59, as show-n in Fig. 12.

When the mortise type of motion transmitting element J isused, then the threaded portion 16 of `the casing B will cooperate with a threaded portion in the door or other structure to be equipped with this ylock to secure the casin-g B in place. On the other hand, when the rim type of motion transmitting element K is being used, then the casing B` is secured in place to the door or structure with which the lock A is i,

to. be equipped by screws cooperating with the openings 1l and 12 respectively.

Obviously, the lock A may be utilized in a variety lof situations, although particularly well adapted for use in hotels. As an example, a guest type of key G may be supplied to the hotel guest and the hotel manager may retain the emergency lock-out key H .so that when the plug C in its normal position, the locking means D and E'may be released by either the guest or the manager whereby to gain access to the room: if the 4guest should fail to pay his or her vhotel bill, the manager may utilize the key H to lockout the guest, so as to force,` the guest to apply to the manager for entrance to the room.`

This may beaccomplished by swinging thev abutment strip 48' toa position alongside the keyblade,` so as Vto unlock the locking means E through the use of only that portion of the keyblade including the bits 'or notches 41. The iront plug section may thus be rotated to its angularposition` as shown by dash lines in Fig. 1, and upon vwithdrawal oi the keyblade, the locking means F will function. The guest, upon his or her return, will find that the guest key G is blocked fromiull insertion in the lock, and, because of the differentiation between the ends of the keys G and H, he or she will find that the plug may `not be turned, andwill call upon the manager to open the door, probably thinking the lock has become jammed. The manager may then tactfully request payment of the hotel bill and then proceed to open the door through the use of the key H, which of course may iirst be utilized in its partially inserted position to unlock the lockstrip 48' so as not to disclose to the guest that a special emergency lock-out key has been used.

If an intruder should. attempt to pick the lock in itsnormally locked position, he would rind it impossible to apply the necessary tension to the rear plug section in order to release the locking means D, as the only access to the rear plug section is through the keyway through which the picking tool must be inserted. Due to the widened base portion of the keyway of the rear plug section and the Ward 3U at the end of the upper portion of the keyway, the use of any instrument or instruments other than a properly bitted key of correct length for unlocking the lo-cking means D and E will invariably prove to be unsuccessful. For example, it has been actually demonstrated that some of the so-called pick-proof locks, such as those embodying independently rotatable front and rear plug sections each having a keyway one alignable with the other, and wherein the keyway of the rear or inner plug section includes a narrow slot communicating with the tumbler openings and an enlarged slot of greater width than that of the corresponding portion of the keyway or the front or outer plug section, can be effectively picked by the modification and use of a readily obtainable key blank and a picking tool. In modifying the key blank, the top or working edge of the blank is removed except for the forward or innermost end of the blank, whereby to leave an inverted V-shaped last rise forming a picking bit. The entire or substantially all of the lower or back marginal edge of the modified blank may then be used as a tension tool, with the last rise or end bit extending upwardly into the narrow portion of the keyway in the rear plug section, so as to join the front and rear sections for ro-` tation in unison. The last rise of the modified key blank may then be reciprocated beneath the innermost pin so as to properly align the latter under tension for a break relative to the casing, the remaining pins being properly aligned by the use of a conventional picking tool disposed in the keyway above the lower or back edge of the modified blank and outwardly of the last rise thereon.

The present invention has not only the widened portion 2l of the keyway -groove which prevents cooperation of a conventional tension tool with the rear plug section 25 due to the resulting lost motion between the tension tool and rear plug section, but also the wall or ward 30 which makes it impossible for a modified key blank tensioningpicking tool to operate the innermost pin as by reciprocation of the end bit or last rise of the modiiied blank past the bottom end of the pin. Obviously, the modified key blank tensioningpicking tool just described, may be readily shaped to pass over an obstacle such as a ward were it disposed only at the inner end portion of the widened base of the keyway in the rear plug section, but where the ward is disposed in the narrow portion of the keyway adjacent the innermost tumbler, the same cannot be picked while under tension` It will be seen that when the locking plug is in its emergency lock-out position, an added barrier confronts the unauthorized intruder, in that the keyways of the front and rear plug sections are disaligned so .that the locking means D may not be reached through the usual keyway.

Any attempt to connect the front and rear plug sections by drilling a hole through the outer plug section and into the inner plug section with the idea of pinning the two sections together, will be frustated by the hardened battling washer 23 closely positioned about the keyhole and formed of drill-resisting material.

Obviously the lock A may be employed solely in conjunction with a key I-I of the emergency lock-out type, where the user desires merely to utilize the added protection against unauthorized intruders which is afforded by the lock in its emergency lock-out position, without sharing the use of the lock with another party through the provision of a guest key.

Various changes may be made to the shape, size and arrangement of parts, without departing from the spirit of the invention or the scope of the following claims.

I claim:

1. In a cylinder lock, a plug including a pair of axially aligning cylinder sections disposed in end to end relation one in front of the other, said cylinder sections each having a keyway one normally in alignment with the other, a casing for the plug, means carried by the casing for locking the front and rear cylinder sections when the keyways are in alignment with each other, additional means carried by the casing for locking the front cylinder section when the keyway of said section is in an annular position relative to the keyway in the rear cylinder section, key-operated means for releasing the front and rear cylinder sections when the keyways thereof are in alignment and for releasing the front cylinder section when the keyways are in disalignment, said keyoperated means being so constructed as to permit the use of a proper key to disengage the front and rear cylinder section locking means simultaneously upon normal insertion into said keyways of said proper key, and to disengage said front cylinder section locking means upon a partial insertion of the same key.

2.y In a cylinder lock, a plug including a pair of axially aligning cylinder sections disposed in end to end relation one in front of the other, said cylinder sections each having a keyway one normally in alignment with the other, a casing for the plug, means carried by the casing for locking the front and rear cylinder sections when the keyways are in alignment with each other, additional means carried by the casing for locking the front cylinder section when the keyway of said section is in an angular position relative to the keyway in the rear cylinder section, key-operated means for releasing the front and rear cylinder sections when the keyways thereof are in alignment and for releasing the front cylinder section when the keyways are in disalignment, said keyoperated means being so constructed as to permit the use of a proper key to disengage the front and rear cylinder section locking means simultaneously upon normal insertion into said keyways of said proper key, and to disengage said front cylinder section locking means upon a partial insertion of the same key, said key-operated means including a tumbler element for releasing the rear cylinder section and comprising a master pin section and a master disc section.

3. In a lock of the character described, a casing including an outer face and having a cylindrical opening extending into the casing from the outer face, said casing being provided with a row of driver-containing chambers extending inwardly of the outer face, a plug rotatable in the cylindrical opening of the casing and hav'mg an inwardly extending row of pin-containing openings corresponding to the row of driver-containing chambers, said plug having a keyway including a marginal zone communicating with the row of openings and adapted to receive the inner end portions of the pins carried in said row of openings, a Ward closing the inner end of the marginal zone, said Ward being disposed from the innermost pin a distance less than the distance between adjacent pins, the remainder of the keyway communicating with the marginal zone and extending beyond said ward.

4. In a lock of the character described, a casing including an outerface yand having a cylindrical opening extending into the casing from the outer face, said casing being provided with a row ofy driver-containing chambers extending in-v wardly of the outer face, a plug including a pair of cylindrical sections positioned in end to end relation in the opening one inwardly of the other, said plug having an inwardly extending row of pin-containing openings corresponding to the row of driver-containing chambers, at least one of said openings being provided in each section, said sections each having a keyway one alignable with the other, the keyvvays of the inner and outer sections each including a marginal space, said marginal spaces upon alignment of the key- Ways forming a zone communicating with the row of openings and adapted to receive the inner end portions of the pins carried in said row of openings, a Ward closing the inner end of the Zone, said Ward being disposed from the innermost pin a distance less than the distance between adjacent pins, the remainder of the key-` Way of the inner section being of a Width greater than the Width of the corresponding portion of pin tumbler locking means normally positioned partly in the casing and partly in the plug at its inner end portion for locking the plug, said plug being provided with a longitudinal keyhole'extending inwardly of the plug 'from its outer end portion and permitting the insertion of a proper key for releasing said locking means, and the outer end portion of the plug being provided with an intra-circumferential slot about the keyhole, a penetration-resistant Washer corresponding to and mounted in the slot, said outer end portion being provided with an annular groove outwardly of said slot, and means carried by the casing extending into said annular groove, said means permitting rotation of said outer end portion and preventing axial movement thereof.

' 6. In a pin tumbler lock, a casing, a key receiving barrel rotatable within said casing, said casing and barrel having alignable bores, pin tumblers each slidably mounted in a set of alignable bores, and each including a driver and a pin, a spring mounted in the casing portion of each alignable bore and engaging the outer end of the driver of each alignable bore, said barrel having a key opening with a longitudinally extending shoulder extending into such opening to receive the key receiving faces of the p-ins in locked position,` a rib extending from the rear end of said barrel and having a bifurcating slot, notches in the portions of saidvrib on opposite sides of said slot, a yieldable retainer cooperating with said'notches to. anchor either the'spindle of a rim `type lock or the cam disk of a mortise type lock said casing having internally threaded screw receiving openings and an external thread, the internally threaded screw receiving openings being adapted to receive screws for anchoring the casing when used as a rim type lock and the external thread being adapted to anchor the casing when. used as a mortise type lock.

BERNARD C. A SMITH. 

